Hi Cyberia - can you help explain something to me? Is the current understanding that the universe did come from nothing? Or that nothing never existed, and that there was no "before" in which nothing could exist?
We can trace time back to 10-43
seconds after the BB. There is high confidence that we can understand events after this point, and no confidence that we can (currently) understand events prior to this. We need a theory of Quantum Gravity to look beyond this point. This is because during this initial period, gravitation effects were significant, if not dominant. Gravity doesn't just affect particles within spacetime, it affects the shape
of spacetime itself. Prior to 10-43
s at least two important events occurred: 1) spacetime was 'created' and 2) spacetime expanded RAPIDLY
, an event known as Inflation. BOTH of these events are related to gravity and occurred in a miniscule universe, hence: Quantum Gravity is necessary.
Now, to answer your question, we don't know.
Current understanding indicates that "time" began at the instant of the BB, T=0. It is not though that this is a limit of our ability to look beyond this point, instead it is a literal beginning of time. There simply was no "before", figuratively or literally. QG will help us understand this issue.
We are also unsure if Conservation of Energy (Thermodynamics) is applicable to the BB or only after the BB. Conservation of Energy is definitely a property of our universe, but that doesn't mean it is necessarily valid "prior" to that or "outside" our universe. Without CoE, Nothing--->Something is most definitely
He wasn't even talking about the Standard Model! He was criticizing general relativity, the popular "model" or "theory" that has lead us to precisely zero technical or technological advancements over the nine decades since its introduction:
He said Standard Model, if he misspoke or if I misunderstood, my apologies.
Now, for what you said, GR has brought about many technological advancements since it's introduction. GPS is one that comes to mind. Those satellites MUST account for relativistic effects or they will become useless within hours. Satellite based gravity maps of Earth wouldn't exist without GR. Communication with remote space probes is adjusted for GR, the space shuttle, the hubble telescope, earth based radar mappings of Venus and Mars must be adjusted for GR